138964440 has 32 divisors (see below), whose sum is σ = 416893680. Its totient is φ = 37057152.

The previous prime is 138964387. The next prime is 138964447. The reversal of 138964440 is 44469831.

It is a happy number.

It is a super-2 number, since 2×138964440² = 38622231169027200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138964447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 578899 + ... + 579138.

Almost surely, 2^138964440 is an apocalyptic number.

138964440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138964440 is an abundant number, since it is smaller than the sum of its proper divisors (277929240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138964440 is a wasteful number, since it uses less digits than its factorization.

138964440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1158051 (or 1158047 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 39.

The square root of 138964440 is about 11788.3179461703. The cubic root of 138964440 is about 517.9659692516.

It can be divided in two parts, 13896 and 4440, that added together give a triangular number (18336 = T₁₉₁).

The spelling of 138964440 in words is "one hundred thirty-eight million, nine hundred sixty-four thousand, four hundred forty".